1. Field of the Invention
This invention relates to revolvers, and in particular to revolvers having a main spring that combines the functions of separate hammer and trigger springs.
2. Prior Art
Conventional revolvers have a frame, a barrel, a cylinder rotatably mounted on the frame rearwardly of the barrel, a hammer pivotally mounted on the frame rearwardly of the cylinder, a trigger pivotally mounted on the frame below the hammer, a hammer spring urging the hammer to its forward or "at-rest" position, and a trigger spring urging the trigger to its forward or "at-rest" position. In a single action revolver the hammer and the trigger are formed with mutually engageable cam surfaces that cooperate to cause the trigger to be rotated from its at-rest position to its ready-to-fire position when the hammer is rotated from its at-rest position to its ready-to-fire position at which position the sear of the trigger engages the sear notch of the hammer to maintain the hammer at its ready-to-fire or cocked position. In a double action revolver the hammer and the trigger are also formed with mutually engageable cam surfaces, the cam surfaces cooperating to cause the hammer to be rotated from its at-rest position to its ready-to-fire position when the trigger is rotated from its-rest position to its ready-to-fire position at which position the trigger releases the hammer to allow the hammer to rotate forwardly under the pressure of the hammer spring and thus to strike a cartridge in the uppermost chamber of the cylinder of the revolver. The mutually engageable cam surfaces of the hammer and trigger of a double action revolver also cooperate to cause the trigger to be rotated from its at-rest position to its ready-to-fire position when the hammer is rotated from its at-rest position to its ready-to-fire position in the same manner as in the case of a single action revolver.
The hammer spring must be sufficiently strong to rotate the hammer forwardly from its ready-to-fire position to its fire position with sufficient force to strike and ignite the primer cap of a cartridge chambered in the revolver cylinder, and the trigger spring must be sufficiently strong to rotate the trigger forwardly from its ready-to-fire position to its at-rest position with sufficient force to overcome the friction and other mechanical forces that impede the return of the trigger to its at-rest position. When the revolver is fired in either its single action or double action mode the trigger and hammer are rotated from their at-rest positions to their ready-to-fire positions against the resistance of both the hammer spring and the trigger spring.
It has heretofore been proposed that the functions of the hammer spring and the trigger spring be combined in a single main spring that is positioned between mutually opposing points on the hammer and the trigger. If the single main spring has sufficient strength, when compressed, to cause the hammer to strike and fire a cartridge chambered in the revolver cylinder, it should have more than sufficient strength to rotate the trigger from its ready-to-fire to its at-rest position against whatever friction and other forces that may impede this movement. In effect, therefore, the need for a separate trigger spring has been eliminated and theoretically both the hammer pull and the trigger pull are reduced by the amount formerly required to compress the trigger spring. Moreover, the elimination of the trigger spring simplifies both the firing mechanism and the initial assembly thereof.
The positioning of a single main spring between mutually opposing points of the hammer and the trigger is effective to some extent in reducing the overall hammer pull or trigger pull required to cock and fire a revolver so equipped. However, the geometry of the parts involved and the space available therebetween has been found to limit the effectiveness of the use of a single main spring to replace the separate hammer and trigger spring. After an intensive investigation into this problem we have found that the effectiveness of the use of a single main spring to replace the separate trigger and hammer spring formerly employed is greatly enhanced by the provision of a generally vertically disposed main spring lever between the single main spring and the hammer. The main spring lever and the connecting linkage associated therewith permit a wide range of adjustments both in the mechanical advantage of the main spring and in the hammer pull and the trigger pull of the revolver. Moreover, our improved firing mechanism is characterized by the essential simplicity of its construction and by the use of a relatively few strongly proportioned parts in place of a greater number of somewhat smaller and less rugged parts.